The SE Racing wheel set is a 20" wheel set that was built to look very much like the old school wheel sets you'd find on so many of the BMX bikes from the 70's and 80's. SE Racing builds these wheels with a fully sealed hub set that uses a 3/8" axle front and rear and is made to work 16t or larger freewheels. The rims are alloy double walled and come in a bunch of colors to match your build. This wheel set is killer for those looking to freshen up a retro bike. Remember that these wheels will NOT work on bikes that use 25t sprockets.